Pitchypoy rigify issue
Appending the rigged object to different scenes doesn't automatically include/run the rig_ui.py script. The script can then be located in the original .blend file's /Text folder.

You can also keep a local copy of the script by generating a new Rigify rig in an empty scene and saving it. Just be sure to change the rig_id in the script to match the rig you wish to generate a UI for before you run it... like this: